I practically live here, it's so good. .-. I've brought all my friends and family members here and now they come all the time too! Their pizzas are no doubt the best in Phoenix, plus they have a local vegetarian pizza too which is a bonus if you really want to support local business!
The owner and the staff are some of the nicest people to work in food service as well. They're very friendly, attentive, and attitude-free (a quality rarely seen in the food industry). Plus, the location is great! It's within walking distance of my house and is also very close to downtown, so you can go there after 1st or 3rd Friday.
They also have specials everyday which is a big motivator to eat there frequently. I give Humble Pie a ten-outta-ten, would eat again.